reporter: 23-year-old paul ciancia lies under guard in a hospital bed, leaving behind a bloody trail to speak for him. >> he made a conscious decision to kill multiple tsa employees. >> the proof, says the fbi, a signed hand-written letter in his bag telling the tsa he wanted to instill fear on your traitorous mind. >> he says if i kill one my mission is accomplished. >> a complaint says he entered terminal three with a bag holding a smith and weston semi automatic rifle with five spare magazines fully loaded. he pulled out the gun and walked up to the tsa checkpoint and fired multiple shots at point-blank range at a tsa officer, and as he moved up thees later he looked back at the wounded officer, who in video appeared to move, and returned to shoot the officer again, killing him. the government shot down at least two more tsa officers before four police bullets put him on the ground. >> it will be the decision of the attorney general of the united states whether or not to seek the death enemy this case. >> gerardo hernandez, the first tsa officer to die in the line of duty. >> he t